Elastic suspension of axle aggregates



Sept; 5, 1944. K., WILFERT 2,357,370

ELASTIC SUSPENSION 0F AXLE AGGREGATES Filed April 4, 1940 1 Sheets-Sheet1 INVENTOR A w/ M/ ATTORNEY p 5; 1944; K. wm'mz 2,357,370

MSTIG SUSPHNSION 0F AXLE AGGBEEATES Filed @111 4, 1940 4 Sheets-Sheet 2INVEN-TO-R B fir/ mytrt Y I. v -woman Sept. 5,1944.

K. WILFERT ELASTIC SUSPENSION OF AXLE AGGREGATES Filed April 4, 1940 4Sheets-Sheet 3 INVENTOR 4 [Vi/fart 'rrbRNEY Sept. 5, 1944. S K. WILFERT7 2,357,370

ELASTIC SUSPENSION 0F AXLE AGGREGATBS Filed April 4, 1940 4 Shets-Sheet4" INVENTOR fir/ Grt a 9 TTORNEY wheels onto the vehicle frame.

Patented Sept. 5, 1944 UNITED STATES PATENT OFFICE.

sms'rro SUSPENSION F AXLE AGGREGATES Karl Wilfert, Sindelflngen,Germany; vested in the Alien Property Custodian Application April 4,1940, Serial No. 327,769 In Germany April 19, 1939 12 Claims.

of the vehicle. but as also comprehending arrangements, known to theart, wherein such body or coach work forms the main vehicle frame itselfor the frame is formed integrally with such body or coach work. Aboveall the invention is important for bodies manufactured of sheet steel,because such steel bodies are specially inclined to vibrations or to aroaring noise, proceeding from the oscillations of the wheels.

A further object of the invention is an elastic connection of thevehicle axles with the vehicle frame in such a manner that, in spite ofinterposing elastic means, a secure position of the car on the road isreached, free of undesirable vibrations, difficult to deal with. Forthis purpose the elastic means particularly are so arranged and providedthat they allow a greater yielding capacity between the axle or acarrier for the axle parts. and the vehicle frame in approximatelyvertical direction, but only a small yielding capacity inlateraldireotion. Specially practical in this case may be thearrangement of the elastic members in such a way, that the main yieldingcapacity between the axle-supporting sub-frame and the main vehicleframe may exist in a direction coincident with the shock direction ofthe wheels. The shock direction principally resultshere by the fact thatthe shock forces arising at the wheel during running have inlongitudinal direction a small horizontal and backward directedcomponent and a larger vertical and upward directed component, so thatthe resulting shock force will be directed steeply upward and backward,deviating from the perpendicular by an angle of to 30.

Furthermore the invention provides an elastic connection of such a kindthat the forces arismain vehicle frame and being preferably so arrangedthat the axes of the bushes extend about vertically and if possible inthe shock direction of the wheels. By arranging two rubberbushes axiallyto each other and in a certain distance from each other, a particularlygood reception of the forces and moments can be obtained.

Furthermore the invention provides an arrangement infwhich the axles ofall wheels, 1. e. the front and the rear wheels of the vehicle areconnected yieldingly with the frame or the body.

By these means the, advantages aimed at will be reached most completely.Eventually the axle piece carrying the wheels yieldingly may beconnected to the vehicle by one or more thrust members, between the axlepiece and the main vehicle frame, elastic members being interposed,allowing a small swinging motion of the axle together with the thrustmember around its pivoting point at the vehicle frame.

In the drawings several types of the invention are illustrated by way ofexample.

Fig. 1 shows a perspective illustration of a car frame in which thefront axle aggregate as well as the rear axle aggregate are yieldinglyconnected to the frame by-means of rubbermetal members.

Fig. 2 shows a. partial sectional view of the rear axle aggregateaccording to Fig. 1, in which the rubber-metal connection between therear axle aggregate-and the frame is shown in section.

Fig. 3 shows a top plan view of the arrangement according to Fig. 2.

Fig. 4 shows a section through the line 4-4 of Fig. 2.

Fig. 5 is a partial view of the front axle aggregate according to Fig.1, in which the rubber metal connection between the front axle aggregateand the frame is again shown in section.

Fig. 6 is a top plan view of the arrangement according to Fig. 5.

Fig. 7 shows a section through the line 1-1 of Fig. 5

Fig. 8 shows a somewhat different form 0:

the rubber metal connection in a sectional vievi within the hollow beamFig. 13 a sectional view of the front axle aggregate, while Fig. 14shows in perspective illustration a somewhat modified form of the frontaxle suspension.

A third type of a vehicle formed in accordance with the invention isillustrated in the Figs. 15 and 16 or 1'7, in which Fig. 15 shows therear axle arrangement,

Fig. 16 the front axle arrangement of this vehicle in side view,partially in section and Fig, 17 a corresponding, somewhat altered frontaxle construction for this vehicle.

In the design according to the Figs. 1 to 7 the main frame is formed bythe longitudinal beams and by the cross beams 2 rigidly connected withit. Furthermore a rear cross beam 3 for the rear axle and a front crossbeam 4 for the front axle is provided, being connected to the frame,interposing a metal connection 5, 6, 1 and 8 to the longitudinal beamsof the main frame.

To the cross beam or sub-frame 3 the differential gear 9 is rigidly oryieldingly connected. To the casing for the gears the swinging semiaxlesIll with the rear wheels H are laterally swivelled. For the shockabsorption serve the spiral springs i2 secured on one side to the crossbeam 3 and on the other side to the semiaxles Ill. The drive istransferred by the motor (not shown) through the Cardan shaft l3 and thedifferential gear 3 onto the swinging semiaxles l0.

The cross beam or sub-frame 4 furthermore carries the front axleaggregate with the steering gear, the front wheels |4 being secured forinstance to a spring carrier H by means of two leaf springs l and 6arranged on top of each stance for the rear axle, is shown in enlargedscale. Preferably the inner sleeve 2| extends from the. middle to bothsides somewhat conical as shown at 29 and 30, receiving in a bore 3| theconnecting bolts (here not shown), for instance the bolt or the bolt 23when applied to the front axle. The inner sleeve 2| is surrounded by therubber sleeve 22 which again is enclosed and held by the outer sleeve23. The outer sleeve has the solid supporting flange 32 and thescrewed-in flange 33 between which for instance the cross-' beams 3 or 4are held. Furthermore the sleeve 23 is so shaped that between the twoflanges 32 and 33 it is cylindrical at both ends, however at 34 it isconical, and more conical than the surfaces 29 and of the inner sleeve.The result will be that the thickness of the rubber sleeve in axledirection is of unequal size, and that according to the size of thearising forces a progressive damping action will take place. At the sametime the loading forces acting in vertical direction will be sure to besecurely received.

With the further designs given e. g. in the Figs. 11 to 14 the frame forinstance consists of longitudinal beams 35 ending in backward formedarms 33 and 31 respectively, arranged in a vertical plane, essentiallyone above the other. In this place however a correspondingly shapedself-supporting body could be used. The frame is similar to the oneshown in Fig. 1, provided with cross beams connecting rigidly thelongitudinal beams, and has at the same time further cross beams onsub-frames 33 and 39 being yieldingly connected to the longitudinalbeams in the manner hereafter described, and serving as car- 'ryingpieces for the rear axle and the front axle: Onto the rear crossbeam 33the rear axle gear 40 is secured rigidly or with interposition of rubberpieces tightened by means of clamping screws or in any other suitableway. The rear wheels 4| are iournaled on the axle cas- 7 ing 40 forinstance by means of pivoted semiother, the carrier being secured to thecross beam 4. To the cross beams 3 and 4 furthermore the shock absorbersl8 are fastened.

The details of the rear axle bearings illustrated in the Figs. 2 and 4show the rubber-metal connection 2|, 22, 23, the inner metal sleeve 2|of which is in connection with the longitudinal frame through the bolt20 and its outer metal sleeve 23, beingin connection with the cross beam3. By these means the rubber sleeve 22 which is securely fastened to thesleeves 2| and 23, for instance by vulcanization, is inserted into thepower transmission between the cross beam 3 and the longitudinal beamsand the small high frequency oscillations which, as is known, cause theroaring noise are kept away from the body.

In the Figs. 5 to '7 the connection of the front cross beam 4 or of thefront axle aggregate to the longitudinal beams of the frame isillustrated. Here the rubber bushing 21 is connected to the longitudinalbeam of the frame by means of an inner metal sleeve 26and a bolt 23, andto the cross beam 4 by means of an outer sleeve 28, the rubber beingpreferably adhesively connected to the metal sleeves by vulcanization.

In Fig. 8, there is illustrated a somewhat altered connection of therear cross beam 3 with one of the longitudinal beams i. In this form,the beams l are hollow and a hollow casing i9 is mounted at each end ofthe beams and attached The bolt 2|) is journaled in the casing l9.

In Fig. 10 the rubber metal connection, f r 1 axles 42 swinginglysecured by cylindrical'pins and supported by unguided spiral springs 43thrusting with their upper end against the ends of the cross beam 38. Onthe'ends of the cross beam also the shock absorbers 44 are arranged.

The yielding connection of the cross beam 33 with the longitudinal beams35 is provided as follows: Between the forked ends 36 and 31 of each ofthe longitudinal beams of the frame conical pins 45 and 46 are insertedand secured by means of screws 41 and 48, serving for the receptlon ofthe conical rubber bushings 43 and '50 which are surrounded by aspecially formed steel sleeve 5|. The arrangement is thus, that the axis52 of the parts 45 to SI forms an angle with the road, amounting toabout the axis 52 extending steeply forward and downward meets the roadbefore the middle of the wheel.

Evidently the entire axle aggregate consisting of the crossbeam 38, thedifferential gear 40, the semiaxles 42, the wheels 4|, the springs 43and the shock absorbers 44 is so connected to the main frame,interposing the rubber bushings 49 and 50, that there is no metalliccontact between the axle aggregate and the frame and the car bodyrespectively. An inclined arrangement of the axis 52 of the yieldingconnection has the advantage that the shocks which the wheel is met withon its course on the road are effective about in the axle direction ofthe rubber bushings so that the yielding capacity of these rubberbushings in their longitudinal direction may fully be made use of. Thedistance between the rubber bushaeeasro lugs 45 and 50 is chosencomparatively great; their guided length, i. e. the distance e of theupper end of the upper rubber bushing 49 from the lower end of therubber bushing 50 amounts to more than half the wheel diameter in theillustrated example, with the efi'ect that the axle aggregate is mostsecurely supported. The rubber bushing 49 may then be within the rangeof the upper wheel covering, and the rubber bushing 50 within the rangeof the lower wheel covering.

The front cross beam 39 is formed essentially as a hollow beam, as shownin Fig. 13, through which the longitudinal beam 35 of the main frame isled, having a vertical bore 53 in the plane of the cross beam. Into thisbore, by means of a metal sleeve 54 a rubber sleeve 55 is inserted beingfor instance vulcanized to this metal sleeve, through which a connectingbolt 55 is led, fastened in the upper and lower walls of the cross beam39. Preferably the connecting bolt is also fastened to the rubber sleeve55 by means of vulcanization. The wheel 51 of the vehicle is guided inparallel by means of the'two guiding levers 55 and 53 which are jointedto the cross beam 39. For the shock absorption of the wheel serves thespiral spring 60 the upper thrust bearing of which is also on the crossbeam at 6|. The bolt 55 may be arranged perpendicular orin a certainangle to the road, for instance corresponding to the shock direction ofthe wheel.

The design according to Fig. 14 is distinguished from the one accordingto Fig. 13 only by the fact that the cross beam 39 is formed of twotubesor rods 62 and 63 connected to each other by the thrust bearing 6|for the springs 60.

With the design according to Figs. 15 and 16 the entire backward drivinggear, consisting of the motor 64, the change speed gear 65 and thedifferential gear 66 is fastened by means of the two bows 81 and 68 tothe metal sleeve 69 made in one or two pieces, and being journalled-.all around yieldingly on the frame 10, similar to Fig. 11. The shockabsorption of the swinging semiaxles ll ensues by means of a laminatedspring 72. The outer covering 13 enclosing the driving aggregate may besecured directly to the subframe in order to avoid a metallic contactbetween it andthe frame and the rest" of the body. I

As shown in Fig. 16 the main frame terminates into a fork the ends 14and of which frame 10 by means of two rubber bushings 88 and or by meansof two pairs of such bushings, having eachshnilarly to the beforementioned examples, a longitudinal axis extending slantingly to theroad, but having in the 'longitudinal direction of the vehicle axes sotransposed relative' to each other that the bushing 85 will be before,and the bushing 88 will be about by the equal amount in back of thewheel cen- 'ter.

The acting direction of the springs 85, 58 lies in this instance in avertical plane, I

In all cases the rubber bushings, as partly described above, can berigidly connected with the parts penetrating or surrounding them, asbolts and sleeves, by means of vulcanization. The connection mayhowever'be made in another suitable manner, for instance by pressing therubber into fittings provided with corresponding flanges. Furthermoreadjusting devices for ad- Justing the angle may be provided, forinstance by forming the pins 45, 43, shown in Fig. 12, in the shape ofeccentrics, or for instance by lengthening or shortening the arms 36, 31in the longitudinal direction of the vehicle by suitable arrangements.Also the pivoting point 82 in the design according to Fig. 16 might bedisplaced for this purpose in vertical direction.

The invention is not limited to the types illustrated and describedabove. Particularly the front and rear axle constructions used for thedifferent designs may b interchanged, and the rear .axle constructionsmay be used as front axle constructions by making correspondingalterations, and vice versa.

Under circumstances it maybe sufllcient if only one of the axlesub-frames willbe connected yieldingly with the main vehicle frame,while the other axle sub-frame is rigidly secured to it. Preferably bothaxl sub-frames will be connected yieldingly with the main vehicle frame.The 'invention may be applied to all kinds of .wheel suspensions,consequently also for rigid 3| which are jointed on one siderespectively by encircling with their sleeve-formed end 33, ex-

tended across the axle member the rubber bushing I1, interposing forinstance a metal bushing 84 which might be vulcanized with it. In thiscase the springs 18 and 19 act in the same direction as the rubberbushing '11 arrangedesing axles, as here the origin of noises andvibrating symptoms is particularly to be apprehended.

The expression sub-frame as used throughout the specification and claimsis to be understood to include not only simple frame means as, forexample, illustrated in the front wheel suspension of Fig. 1, but alsoto include such constructions as shown, for example, in the rearsuspension in Fig. 1 in which the drive gear casing is combined andrigidly attached to the cross beam, and also constructions, such asillustrated in Fig. 15, wherein the sub-frame also includes the drivingengine, speed-change gearing and senti'ally tangentially to the swingingradius of I the pertaining thrust member 8|, inorder to have the fullbenefit of its comparatively great yielding capacity inthe axledirection of the bushing. The thrust member 8l' may bearranged in thelongitudinal center plane of the vehicle for instance at a crossbeam. Asalready hinted at, two thrust members at both the drive gearing, allconnected with one another as a drive unit.

As th main frame a usual frame formed of longitudinal and cross beamsmay beused or for instance a frame consisting of a central longitudinalbeam, extending eventually at one or at both ends into a frame fork withtwo lateral fork arms, which may be understood by the expression oflongitudinal frame beam." The term main frame as used throughout thedescription and claims is also to be understood to cover thoseconstructions in which the body itself of the vehicle forms the mainvehicle frame, as, for example, in the so-called well-known "frameless"vehicles.

Having now particularly described and ascertained the nature of myinvention and in what manner the same is to be performed, I declare thatwhat 'I claim is:

1. In a vehicle having a main frame which includes a pair ofsubstantially longitudinal beams, formed with forked extensions at theirends. a sub-frame member resiliently connected and mounted transverselyto said beams in said forked extensions, a pair of swinging half-axlespivetally connected to said sub-frame member for relative up and downmovement, spiral springs intermediate said half-axles and said sub-framemember, and ground-engaging wheels on said half-axles.

2. In a vehicle havin a main frame, a subframe member, ground-engagingwheels resiliently connected to said sub-frame member for relative upand down movement, and means for resiliently connecting said sub-framemember to said main frame comprising a pair of devices each consistingofa pair of concentric metallic sleeves with an elastic sleeve pressedbetween 'them, a bolt passing through the inner sleeve for attaching thesame to said main frame, and a pair of axially displaced flanges on saidouter sleeve holding the sub-frame member between them.

3. The combination according to claim 2, in

which one of said flanges is threadably attached.

each hollow beam, and means for resiliently 6011-. necting saidsub-frame member to said main frame comprising a pair of devices eachconsisting of a pair of concentric metallic sleeves with an elasticsleeve pressed between them, a bolt passing through the inner sleeve forattaching the same to and within said hollow casing, and means forattaching said sub-frame member to each outer metallic sleeve.

5. The combination according to claim 4, in which said last meansincludes a pair of axially spaced flanges on said outer metallic sleeveholding the sub-frame member between them.

6. The combination according to claim 2, in

which the means for resiliently suspending the ground-engaging wheels tothe sub-frame member includes swinging half-axles pivotally connected atone end'to said sub-frame member and supporting a ground-engaging wheelat its other end, and spring means intermediate each halfaxle and saidsub-frame member.

7. The combination according to claim 2, in which said main frameincludes a pair of substantially longitudinal beams formed with forkedextensions at their ends, and in which said subframe member ispositioned in said forked extensions and connected to th same throughsaid devices.

8. The combination according to claim 2, in

I which said sub-frame member includes a drive gear casing, and themeans for resiliently suspending said ground-engaging wheels throughswinging half-axles pivotally connected to said casing, and springingmeans intermediate each half-axle and the sub-frame member.

9. In a vehicle frame having a main frame, a sub-frame member,ground-engaging wheels resiliently supportin said sub-frame member forrelative up and down movement, and means for resiliently interconnectingsaid main frame and sub-frame member, comprising a pair of devicesconsisting of a pair of concentric metallic sleeves with an elasticsleeve pressed between them, a bolt passing through the inner sleeve forattaching the same to said main frame, and a pair of axially displacedflanges on the outer sleeve holding said sub-frame member between them.

10. In a vehicle havinga main fram provided with a plurality of pairs ofears, a sub-frame member, and means for resiliently connecting saidmember to said main frame, comprising a plurality of pairs of concentricsleeves, one sleeve of each pair being mounted in one of the pairs ofears on the main frame, and th other sleeve of each pair having meansfor gripping one end 'of said member, and a'resilient sleeve disposedbetween the sleeves of each of said pairs and attached to its adjacentsleeves.

11. In a vehicle havin a main frame which includes a pair oflongitudinal beams, each formed with a forked end, a sub-frame member,and

means for resiliently connecting said member with said frame, comprisinga plurality of pairs of concentric sleeves, one sleeve of each pairbeing mounted in one of said forked ends, and the other sleeve of eachpair having means for gripping one end of said member, and a resilientsleeve disposed between the sleeves of each of said pairs and attachedto its adjacent sleeves.

12. In a vehicle, the combination according to claim 10, the resilientsleeves tapering conically in at least one direction.

KARL WIIFERT.

